This invention relates to a low cost, self-contained system for driving a rotary hydraulic motor or the like, which requires only a supply of water in a water reservoir, tank or the like, as a power source.
Thus, the power system in accordance with the invention includes a pair of hydraulic cylinder assemblies each disposed in vertical disposition below a common water source, the respective cylinder heads being interconnected by hydraulic delivery and supply conduits in a clossd circuit including a rotary hydraulic motor or like driven member which is operated by forward and reverse flow of liquid through the circuit effected by respective flow cycles each comprising sequential filling of one cylinder with the liquid and raising of its piston accompanied by lowering of the other piston and emptying of its cylinder followed by emptying of the one cylinder and filling of the other, the upper ends of the respective pistons being provided with water tanks which are filled from said water source and emptied into respective discharge tanks sequentially in each cycle to provide lowering and allow raising of the pistons respectively in their respective cylinders. The system further includes various valve devices in the closed hydraulic circuit and in association with the water source and pistons and discharge tanks for controlling the respective liquid flows in a manner effecting cyclical reciprocation of the respective pistons as aforesaid.
The system is substantially maintenance free, and can provide continuous low cost operation of a rotary hydraulic motor, for example, which can be used inter alia to drive an electric generator, or as a direct power source. No fuel or outside power is required for the system which includes a minimum of moving parts.